Those are the three words Rolling Stone uses to describe teen pop phenom Justin Bieber on the cover of its August 2 issue. And the "Boyfriend" singer, 18, seems perfectly at ease wearing those three labels. "I'm definitely more mature. I feel like I carry myself in a more manly way," Bieber explains. "I don't carry myself as a boy."

(As it happens, Rolling Stone already used the "Hot. Ready. Legal." tagline on another cover story for another teen phenom back in 2004: Lindsay Lohan.)

Though Bieber is known for pulling more than a few pranks, he's anything but unprofessional. "When he's being a prick, it's not because he's famous," the singer's manager, ScooterBraun, says. "He's being a prick because he's a kid."

The Canadian-born star has come a long way since the 2009 release of his debut album, My World: He graduated from high school, got his first credit card and fell in love for the first time.

When it comes to his relationship with former Disney Channel star Selena Gomez, Bieber says he's pretty romantic. "I make sure to do the little things," he reveals. "Like noticing when they get their hair done, or when they change their nail color. Also saying things all the time — like, 'You're very pretty,' 'You're gorgeous,' things like that."

Braun dispels the idea that Bieber's relationship with Gomez, 19, will lessen his appeal with tween fans. "Personally, I think that's all a bunch of bullsh-t," Braun tells Rolling Stone. "Yes, there's gonna be some girls that if they see him with a girlfriend, it kills the dream — but there's also gonna be girls that see him with a girlfriend, hear about the romantic things he does and want him even more."

To see more photos of Justin Bieber and read the full interview, pick up the new issue of Rolling Stone, on stands Friday.